Method of dissolving liquefied gas and apparatus therefor

ABSTRACT

Dispersing apparatus achieves solution of a soluble liquefied gas in a liquid solvent while permitting at least substantially full pressure on the liquefied gas to the point of incipient solution and thereafter affords desirable dispersion of the liquefied gas dissolving the solvent as well as providing fast and efficient flow of the resulting solvent into a liquidprocessing medium. The apparatus provides for suppressed vaporization of gas, even though such suppression occurs during an accompanying pressure drop, when the liquefied gas dissolves in the solvent, and further when the resulting solution disperses in the liquid-processing medium.

United States Patent [72] Inventor Udell T. Greene 2,312,639 3/l943Gronemeyer 259/4 Florham P rk, NJ. 2,740,616 4/1956 Walden 259/4 [21]Appl. No. 832,633 3,330,535 7/1967 Stengel 259/4 [22] Wed June 1969Primary Examiner-William 1. Price 3; g f 'f 3 k C Attorneys-C. ThomasCross, Roy Davis, Timothy E. Tinkler, Sslgnee amen alflmc orporatlonJohn .I. Freer, Sam E. Laub, Neal T. Levin, Leslie G. Nunn, ClevelandOhm Jr., Helen P. Brush and John C. Tiernan LIQUEFIED GAS AND ABSTRACT:Dispersing apparatus achieves solution of a solu- 5 Claims 4Drawin s bleliquefied gas in a liquid solvent while permitting at least g lgsubstantially full pressure on the liquefied gas to the point of [52]U.S.Cl. 259/4 incipient solution and thereafter affords desirabledispersion [5 l] Int. Cl B0ll' 1/00; of the liquefied gas dissolving thesolvent as well as providing BOlf 3/04 fast and efficient flow of theresulting solvent into a liquid- [50] Field of Search 259/4 processingmedium. The apparatus provides for suppressed va rization of as, eventhou h such su ression occurs dur- [56] References Cited ing zn accompanying pressur drop, wl z n the liquefied gas UNITED STATES PATENTSdissolves in the solvent, and further when the resulting solu- 2,307,5091/1943 Joachim et'al 259/4 ti n disperses in the liquid-processingmedium.

33 3 22 4 I 4 1| 4 23 2s 9 5 n y I 32 x 33 PATENTED JUN 1 I971 INVENTORUDELL I GREENE ATTORNEY METHOD OF DISSOLVING LIQUEFIED GAS AND APPARATUSTHEREFOR BACKGROUND OF THE INVENTION The introduction of a solubleliquefied gas into a liquid solvent can often lead to flashing of theliquefied gas and thus to the formation of discrete gaseous bubbleswithin the solvent. Moreover, where such resulting solution of liquefiedgas is thereafter injected into a liquid processing medium the pressuredrop commensurate with such injection may lead to further flashingwithin the liquid processing medium. Thus at both the introduction ofthe liquefied gas into the solvent and of the resulting solution intothe processing medium retarded solution efficiency and prolongedsolution time and hence undesirable pro'cessing efficiency can often beencountered.

This may be a particular problem with a substance which is normallygaseous at standard temperature and pressure and thus may be under apressure of 2-3 atmospheres or greater when in liquid condition.Therefore, although solution is slower, many substances which aretypically shipped and/or stored in the liquid state may be permitted tobecome gaseous before combining with a solvent.

SUMMARY OF THE INVENTION Dispersing apparatus is now provided whichaffords direct introduction of the liquefied gas into a stream of liquidsolvent. Next the dispersing apparatus provides for enhanced dispersionof the-liquefied gas as it dissolves in the solvent and subsequentlyprovides for excellent dispersion of the resulting solution into aliquid processing medium, all the while suppressing flashing of gaswithin the apparatus. Moreover the apparatus permits at leastsubstantially full pressure on the liquefied gas to the zone ofincipient solution in the solvent.

Broadly, the dispersing apparatus of the present invention comprises aconduit confining a stream of the liquid solvent; a single-seated, valveassembly, having a valve passage therethrough forming a part of theconduit, the valve assembly having means whereby a controlled flow ofsoluble liquefied gas is introduced directly into the stream of solventflowing within such passage; mixing means downstream from the valveassembly, enhancing dispersion of the soluble liquefied gas dissolvingin the solvent; and a nozzle assembly downstream from such mixing meansfor passing the resulting solution into the liquid processing medium.

The foregoing single-seated valve assembly comprises a valve body havinga valve passage therethrough connecting spaced-apart inlet and outletports, and forming a portion of a conduit confining the liquid solvent,with the body having two hollow side protrusions, the first of whichextends outwardly from the body between the ports, and the second ofwhich extends outwardly from the valve body at least substantiallycoaxial with the first and opposite same across the valve passage. Asubstantially rigid, stationary valve seat forms with the firstprotrusion a side passageway terminating in an end port opening at anend surface of such valve seat, with the end surface being positioned sothat the end port opens directly into the valve passage at least along awall thereof.

A movable'valve stem within the second protrusion opposite-such end portand across the valve passage, terminates in an end section adapted forat least partial insertion within the end port and for sealing thereof.The end section has at least one beveled surface longitudinally alongsame providing diminishing cross-sectional area for the end sectiontoward the endport. The valve assembly lastly has means for reciprocallytransporting the shaft to remove and insert the end section within theend port. Thus the end section seals the end port when in snugengagement therewith and the beveling of the end section permits fluidto flow from the end port into the valve passage in amounts increasingwith the increasing removal of the shaft from the side passageway.

The invention is further directed to a method of first dissolving asoluble liquefied gas into a liquid solvent and thereafter dispersingthe resulting solution into a liquid processing medium. The invention isfurther most particularly directed to use with substances which arenormally gaseous at standard temperature and pressure and are oftenavailable in liquid condition, such as sulfur dioxide and chlorine, thatcan be first dissolved in concentrated solution and the solutionemployed in subsequent processing medium, e.g., a concentrated aqueoussolution of chlorine for bleaching a pulp stream or a concentratedaqueous solution of sulfur dioxide for treating an industrial wastewater.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view ofrepresentative dispersing apparatus of the present invention.

FIG. 2 is a sectional view of a portion of a representative valveassembly for apparatus of the present invention.

FIG. 3 is a sectional view of an orifice plate assembly useful in theapparatus of the present invention and taken along the line 3-3 of FIG.I, as viewed in the direction indicated by the arrows.

FIG. 4 is a sectional view of a nozzle assembly for the apparatus of thepresent invention taken along the line 4-4 of FIG. 1 and viewed in thedirection indicated by the arrows.

DESCRIPTION OF THE PREFERRED EMBODIMENT In the dispersing apparatus ofFIG. 1 fluid feeding from a source not shown first enters a valveassembly containing a valve housing 5 having a valve passagetherethrough, not shown. From the valve housing 5 there extends a sideprotrusion 6 containing a side conduit 7 provided with an inlet channel8. The valve body 5 has a second side protrusion 9 housing a guide ring11 around a movable valve stem 12 connecting to operating means, notshown. The valve assembly is connected to mixing apparatus containingperforated plates 22, spaced apart one from the other by hollowcylindrical sections 25, and maintained in place by flanges 23. A hollowconical section 24 connects the mixing apparatus with the valve assemblyand a hollow conical section 24 also connects the mixing ap paratus withthe balance'of the dispersing apparatus. This balance of the dispersingapparatus consists of a nozzle assembly positionedaround a conduit 31.The nozzle assembly contains a second annular member 32 maintainedbetween radial flanges 33.

Referring to FIG. 2, the side conduit 7 within the side protrusion 6terminates in a valve seat 13. The valve seat 13 contains an end port 14at the top of the inlet channel 8, and the valve seat 13 extends intothe valve passage 20. The end section of the valve stem 12 terminates ina finger 15 extending from a shoulder 16'around the valve stem 12. Thevalve seat 13 ends in an end surface 17 opposite a coplanar end surface18 of the shoulder 16. The finger 15 is provided with a beveled surface19 extending along the finger l5 and affording diminishingcross-sectional area away from the shaft 12. For this assembly, it canbe seen that the zone of incipient solution for liquefied gas enteringthe solvent includes the region where solvent flows between the coplanarsurface 18 and the valve seat end surface 17 and around the portion ofthe finger 15 emerging from the end port 14.

In FIG. 3 the perforated plate 22 contains apertures 26 through theplate 22 and is positioned behind a flange 23 having bolting holes 28through same. In FIG. 4, a second annular member 32 has an inner surface38 and further has bolting holes 34 extending through the member 32 froma radial flange 33. The second annular member 32 surrounds a firstannular member 35 having an outer surface 39 from which slots or ports36 extend through the first annular member 35.

Between the outer surface 39 of the first annular member35 and the innersurface 38 of the second annular member 32, a portion of the radialflange 33 forms with such annular members 32, 35 an annular opening 37.

Referring again to FIGS. 1 and 2, liquid solvent feeding from a sourcenot shown enters the valve housing 5 in a direction as shown by thearrow. As the liquid solvent flows within the valve passage 20 it flowsaround the valve seat 13 and across the portion of the end surface 17 ofthe seat 13 not engaged by the coplanar end surface 18. The liquidsolvent is at a pressure substantially as great as, to higher than, thevapor pressure of the liquefied gas, to be introduced into the solvent,based on the temperature of the solvent. Liquefied gas feeding from asource not shown and at a pressure above that of the solvent within thevalve housing 5 is fed through the inlet channel 8 into the end port 14and thus into contact with the finger within the end port 14. Withdrawalof the valve stem 12 permits a flow of the liquefied gas from the endport 14 along the beveled surface 19 of the finger 15 and into immediatecontact with the flow of liquid solvent within the valve passage 20.Reverse movement of the valve stem 12 places the coplanar end surface 18of the stem 12 back in snug engagement with the end surface 17 of thevalve seat 13 thereby sealing the .end port 14.

As shown in FIG. 1 and FIG. 3, the liquid solvent passing from the valvehousing 5 and containing the dissolving liquefied gas flows throughhollow conical section 24 and then through apertures 26 in a series ofperforated plates 22 spaced apart by hollow cylindrical sections 25.Referring then to FIG. 1 together with FIG. 4, resulting liquid solventcontaining an enhanced dispersion of dissolved liquefied gas thereinflows from a hollow conical section 24 of the mixing apparatus and intoan annular opening 37 in the nozzle assembly. The resulting solutionwithin the annular opening 37 then continues through the slots 36 in thefirst annular member 35 and feeds into liquid processing medium flowingwithin the conduit 31.

The valve assembly need not be directly connected to the mixing meansbut can be spaced apart therefrom by a conduit. The mixing means can beany mixing means employed for enhancing the solution of a dissolvingliquid solute in a liquid solvent such as mechanical mixing means, e.g.,typically propeller-agitated tanks, pumps including centrifugal pumps,and turbine mixers, as well as being hydraulic mixing assemblies such asan orifice column or turbulence mixers including the baffle plate mixersthat may have a column diameter, or the like, the same as the valvepassage diameter. Moreover, the feed from the valve assembly can bedivided and passed through a number of mixing apparatus in parallel. Thenonle assembly for introducing the resulting solvent from the mixingapparatus can also be one or more injector means which need not becircular but can have other cross-sectional shape. Moreover, the slotsor ports in the inner or first annular member can be one or more slotswhich may be radial or at varying angles to radius lines and unevenlyspaced.

The feed from the mixing apparatus to the nozzle assembly can enter samethrough the outer annular member such as in radial or tangential manneror can be divided and enter the nozzle assembly through more than oneentry port in the radial flanges or outer annular member or both. Also,where perforated plates are employed in the mixing apparatus, each platemay have one or more holes and the holes can have axes which are nottransverse to the plane of the plate. Typically the side flanges of thenozzle assembly are integral with the conduit through which theprocessing medium flows and the inner annular member of such assembly isfastened to the flanges by cementing or welding, which can includesolvent welding when assembly parts are receptive to same. However, anyother conventional fastening means may be employed, for example, theinner annular member can have an inner lip extending around and withinthe conduit, thereby holding it in place.

The end surface of the valve seat should be at least along a wall of thevalve passage to insure introducing the liquefied gas directly intocontact with the solvent liquid flowing within the valve passage. Also,the side protrusions of the valve body need not be at the midsectionthereof and need not be transverse to the valve passage but can becanted either against the flow of the liquid solvent within the passageor away from same, so long as these protrusions are substantiallycoaxial with one another across the valve passage to permit sealing ofthe end port with the end section of the shaft. Preferably, the sideprotrusions are completely solid and/or filled up to the wall of thevalve passage thereby preventing flow of solvent liquid into such sideprotrusions. The beveled surface for the end section of the shaft, orvalve stem, can be more than one such surface or a beveled surfacecompletely around such section, as a conical surface, e.g., so that thefinger in FIG. 2 is a truncated cone. Also, the end surface of the valveseat need not be flat but can be a rounded surface projecting into thevalve passage.

The dispersing apparatus can be typically employed in commercialoperation involving the introduction of a soluble liquefied gas such aschlorine into an aqueous medium to form a concentrated solution whereinthe downstream use in the processing medium might simply be waterpurification, or liquid chlorine into a liquid hydrocarbon, or aconcentrated liquefied carbon dioxide solution in water for downstreamintroduction into a liquid beverage concentrate, or liquefied sulfurdioxide first into water and then the solution into waste waters, e.g.,industrial waste waters. In the special application of liquid chlorineinto an aqueous medium, such medium can typically be at a temperaturewithin the range from about 35: -l20 F. and under a pressure of betweenabout 20-200 p.s.i.g. For such conditions the pressure on the liquidchlorine is advantageously between about l040 p.s.i.g. above thepressure of the aqueous medium although greatly higher pressuredifferences, e.g., p.s.i.g. or more, are operational. A pressuredifferential below about 10 p.s.i.g. can provide inefficientintroduction of liquid chlorine into the aqueous medium and a pressuredifferential above about 40 p.s.i.g. over an extended period may lead toa jet effect within the valve assembly and deleterious mechanicalerosion of assembly parts.

For the application wherein the processing medium is a suspension ofpulp in a liquid medium and an aqueous chlorine solution is used inbleaching the pulp, the pulp suspension is typically at a pressure ofbetween about l080 p.s.i.g., which pressure is established substantiallyby the hydrostatic head of the bleaching tower and by the frictionpresented in the apparatus piping from the introduction of the aqueouschlorine solution to the point of entry for the suspension into thetower. The pressure of the aqueous chlorine solution before feeding intothe pulp suspension is typically above the vaporization pressure for theliquid chlorine at the temperature of the aqueous medium and for theconcentration of the chlorine therein. For example, with an aqueousmedium at 100 F. and for a saturated solution, the pressure establishedon the aqueous chlorine solution is typically above about I42 p.s.i.g.,whereas for such saturated conditions where the temperature of theaqueous medium is at F. the pressure would be above about I88 p.s.i.g.

However, when the liquid chlorine is introduced into the aqueous medium,the apparatus provides that elevated pressures above the pressure atwhich chlorine will vaporize need not be attained for excellentsuppression of chlorine vaporization. For example, results have shownthat at a water temperature of l07 F. and a pressure of I50 p.s.i.g.,under which conditions of temperature and pressure liquid chlorine canotherwise be expected to vaporize, virtually no deleterious formation ofchlorine vapor has been experienced with such apparatus. Nonetheless, itcan be seen from the foregoing that pressure differentials between theaqueous chlorine solution and the pulp suspension for water temperaturesfrom 100- 120 F. can be up to about p.s.i.g. or more.

For this typical application, i.e., of chlorine into water and thenchlorine water into a pulp suspension, the entire surface area of thevalve assembly exposed to the liquid chlorine or to the liquid chlorinedissolving in the water is best provided by a vinylidene fluoride resinor a fluorinated ethylene-propylene resin. At the elevated pressures forthe liquid chlorine, e.g., approaching 200 p.s.i.g., a fluorinatedethylene-propylene resin valve seat such as the valve seat 13 in FIG. 2can show some deflection under pressure which, when the pressure isrelaxed, will return to a normal state. For example, the inner sectionof the valve seat 13 around the entry port 14 in FIG. 2 can be displacedslightly inwardly toward the center of the valve passage 20. Thus thevalve seat can be somewhat flexible. The balance of the apparatusdownstream of the valve assembly, i.e., the mixing means and nozzleassembly, may then be any of the materials useful for confining anaqueous solution of chlorine, e.g., ceramic lined apparatus andpolyvinyl chloride lined apparatus, or elements such as the annularmembers of the nozzle assembly can be completely fabricated fromtitanium or polyvinyl chloride or the like.

More particularly, in referring again to the drawings, water under apressure of l 15 p.s.i.g. and at a temperature of 73 F. is passedthrough the valve passage at a rate of 6.6 gallons per minute. As thevwater is flowing through the valve passage 20, the end port 14 of thevalve seat 13 is closed by the end sectionof the valve stem 12.Thereafter the valve stem 12 is gradually moved upwardly so that liquidchlorine, feeding into the end port 14 of the valve seat 13 at apressure of about I75 p.s.i.g. is fed through the valve port l4 into thevalve passage 20. Such feed is gradually increased to a chlorine feedrate of 1.0 pound per minute.

The liquid chlorine dissolving in the water in the valve passage 20 isfed downstream through a pipe having a constant inside diameter the sameas the valve passage except that the pipe contains four perforated plate22 placed between hollow cylindrical pipe sections 25. Each perforatedplate 22 has a single aperture 26 which decreases the inside pipediameter by a factor of one-half. This mixing apparatus was constructedso that the flow of the liquid therethrough could bevisually inspectedfor chlorine flashing and/or hydrate formation. In a conduit'3l havingan inside diameter three times as great as the inside diameter of thehollow cylindrical sections there is fed 62 gallons per minute of waterat a temperature of 73 F, and a pressure of 13 p.s.i.g. The solution ofchlorine in water is fed from the mixing assembly into an injectorassembly and flows from the injector assembly through a single orificehaving a 3/l6-inch diameter. The conduit 31 simulating a conduit forcarrying a pulp slurry is also constructed for visual inspection ofchlorine flashing and/or hydrate formation within the conduit. Duringoperation both the mixing assembly and the conduit 31 are thus visuallyinspected and no chlorine flashing or hydrate formation is visuallyobserved, although hydrate formation would not be expected. Some gas isvisually observed to be present in the conduit 31 downstream from theinjector assembly but such gas is not regarded as significant and is notobserved to be attributed to chlorine flashing.

Moreover the flow from the conduit 31 is collected, chlorine dissolvedtherein neutralized by sodium hydroxide, and the neutralized mediumanalyzed to determine actual chlorine content in the conduit'3l outflow.By this method and by comparing the results with the flow of chlorineinto the valve passage 20 from the end port 14, it is found that 98percent of input liquid chlorine is contained in the liquid outflow fromthe downstream conduit. These results are deemed to be excellent and theapparatus is regarded as highly suitable for bleaching of pulpsuspensions.

Another run is made with the apparatus with water passing through thevalve passage 20 at a temperature of 40 F. and a pressure of 80p.s.i.g.at a rate of 5 gallons per minute. Liquid chlorine entering the end port14 at a temperature of 83 F. and a pressure of about 165 p.s.i.g. is fedinto the water within the valve passage 20 at a rate of 1.5 pounds perminute. At such a rate the chlorine feeding into the water at the valveas well as in the downstream mixing apparatus is in an amount of 0.3pounds per gallon of water. Under these conditions there is observed byvisual inspection to be no chlorine flashing and to be no noticeableformation of chlorine hydrate, even though with a water temperature of40 F. and a pressure of 80 p.s.i.g., a chlorine content of 0.3 poundsper gallon in water can be expected to provide appreciable amounts ofhydrate formation. The conditions under which hydrate formation, i.e.,Cl: -8H,O formation, can be expected, may be best understood byreferring to the data presented, for example, in Perry, ChemicalEngineers Handbook, 3rd Edition, page 674 and recharting such data, asequal pressure lines, on a chart showing solubility of chlorine in watervs. temperature of the water.

The solution leaving the mixing assembly is passed into the pulpsimulator conduit 31 through which conduit water at a pressure of 14p.s.i.g. and a temperature of about 72 F. is flowing at a rate of 62gallons per minute. Since no visual chlorine vaporization or hydrateformation is found by visual observation of the apparatus, the apparatusis deemed in addition to being excellently suited for the chlorinebleaching of a pulp suspension to also be excellently suited for suchoperation free from chlorine vaporization and hydrate formation wheresuch might otherwise be expected.

For the typical application of dissolving chlorine into an aqueousmedium and then feeding the resulting solution into a pulp suspension,the ports or slots through which the solution feeds into the suspension,where such ports are at least essentially circular in cross section,they have a diameter advantageously on the order of about three-eighthinch or less to enhance fast dispersion of such solution into the pulpsuspension. The size employed for each slot or port, which size can varyfrom port to port, will be dependent upon the number of ports availableand the flowof chlorine solution desired into the pulp suspension, whichin turn will be dependent upon the pressure drop. For example, with apulp suspension at a pressure of about 30-35 p.s.i.g. and an aqueouschlorine solution at a pressure of about ll0-l25 p.s.i.g., a circularport of 0.25-inch diameter will pass about 10 gallons per minute ofchlorine solution into the pulp suspension. The number of such 14-inchslots thus employed will then depend upon the total amount of suchsolution desired to be passed into the pulp suspension for a given timeperiod, which in turn can be readily determined by the concentration ofchlorine in the aqueous solution and the desired concentration ofchlorine in the treated pulp suspension.

Although the total amount of the liquefied gas which will be introducedinto the liquid solvent is dependent upon a number of factors includingtype of solvent and type of liquefied gas as well as the pressure underwhich the solvent is flowing through the valve passage, for the typicalintroduction of liquid chlorine into an aqueous medium at a pressure forexample of p.s.i.g., useful solutions of liquid chlorine in aqueousmedium typically contain not substantially above about 0.5 pound ofchlorine per gallon of aqueous medium. Moreover, the amount of dissolvedliquefied gas that should be present in the liquid processing medium canalso bedependent upon a number of factors such as those discussedhereinabove. For the typical introduction of liquid chlorine into waterand for introduction then of the dissolved chlorine in the water into apulp stream the desired amount of chlorine is almost always not aboveabout 20 weight'percent and is typically 10 weight percent or less, suchpercent being based on the total downstream weight of the dry pulpcontent In conventional pulping operations such content is oftendesirably between about 37 weight chlorine by weight of the dry pulpcontent of the slurry.

It is to be understood that, although the invention has been describedwith specific reference to particular embodiments thereof, it is not tobe so limited, since changes and alterations therein may be made whichare within the full intended scope of this invention as defined by theappended claims.

I claim:

1. Dispersing apparatus for first dissolving a soluble liquefied gasinto a liquid solvent while permitting at least essentially fullpressure on the liquefied gas to the zone of incipient solution, andthereafter dispersing the resulting solution into a liquid processingmedium with accompanying pressure drop, while suppressing vaporizationof gas as said liquefied gas dissolves in said solvent and as theresulting solution disperses in said liquid processing medium, whichapparatus comprises:

1. a conduit confining a stream of the liquid solvent;

2. a single-seated valve assembly, having a valve passage therethroughforming a part of said conduit, said valve assembly having means wherebya controlled flow of soluble liquefied gas is introduced directly intosaid stream of solvent flowing within said passage;

. mixing means downstream from said valve assembly, enhancing dispersionof the soluble liquefied gas dissolving in said solvent; and

4. a nozzle assembly downstream from said mixing means for passing theresulting solution into said liquid processing medium;

wherein said single-seated valve assembly comprises:

A. a valve body having a valve passage therethrough, connecting spacedapart inlet and outlet ports, and forming a portion of said conduit;

B. a first hollow side protrusion extending outwardly from said bodybetween said ports;

C. a second hollow side protrusion extending outwardly from said valvebody, at least substantially coaxial with said first protrusion andopposite same across said valve passage;

D. a substantially rigid, stationary valve seat forming with said firstprotrusion a side passageway terminating in an end port opening at anend surface of said seat, said end surface being positioned so that saidend port opens directly into said valve passage at least along a wallthereof;

E. a movable shaft within said second protrusion, opposite side end portacross said valve passage, said shaft terminating in an end sectionadapted for at least partial insertion within said end port and forsealing thereof, said end section having at least one beveled surfacelongitudinally along same providing diminishing cross-sectional area forthe end section toward the end port; and

F. means for reciprocally transporting said shaft to remove and insertsaid end section within the end port;

whereby said end section seals said end port when in snug engagementtherewith, and the beveling of said end section permits fluid to flowfrom said end port into said valve passage in amounts increasing withthe increasing removal of said shaft from the side passageway.

2. The dispersing apparatus of claim 1 wherein said mixing means ishydraulic and comprises a column containing spaced-apart plates, eachplate being positioned partly to completely within said column and atleast substantially transverse to the direction of flow of liquidtherein, each plate containing at least one aperture whereby said liquidflows through said plate.

3. The dispersing apparatus of claim 1 wherein said liquid processingmedium flows through a second conduit and said nozzle assembly comprisesat least one disperser ring, around the second conduit, and comprising:

1. a first annular member having an inner diameter substantially thesame as the diameter of the second conduit with the inner surface ofsaid member forming a portion of said conduit, said member having atleast one slot extending through same from the outer surface thereof toits inner surface;

2. a second annular member positioned coplanar and coaxial with saidfirst annular member and having an inner diameter substantially greaterthan the outer diameter of said first annular member thus providing anannular opening between said members;

3. radial flanges each engaging both said first and second annularmembers along the'radial side surfaces thereof across said annularopening, thereby enclosing the opening; and

4. inlet means for feeding the resulting solution from said mixing meansinto said annular opening, whereby it flows through the slot of thefirst annular member and into the liquid processing medium passingthrough the second conduit.

4. The dispersing apparatus of claim 1 wherein the end section of saidvalve assembly shaft comprises a finger extending from a shoulder aroundsaid shaft, said finger being insertable within said end port and havingat least one nonbeveled surface adapted to provide snug contact betweensaid finger and the surface of said end port until complete removal ofthe finger therefrom, said shoulder having at least one surface incoplanar relation with the end surface of the valve seat, whereby saidshoulder seals said end port when said coplanar surface abuts firmlyagainst the end surface of the valve seat.

5. The method for first dissolving a soluble liquefied gas into a liquidsolvent while permitting at least essentially full pressure on theliquefied gas to the zone of incipient solution, and thereafterdispersing the resulting solution into a liquid processing medium withaccompanying pressure drop, while suppressing vaporization of gas assaid liquefied gas dissolves in said solvent and as the resultingsolution disperses in said liquid processing medium which methodcomprises:

A. passing said liquid solvent within a valve passage housed in a valvebody, at a pressure substantially as great as, to higher than, the vaporpressure of said liquefied gas at the temperature of said liquidsolvent;

B. feeding soluble liquefied gas into a side passageway of said valvebody at a pressure above that of the liquid solvent in the valve passageand into contact with a shaft end section sealing an endport of saidside passageway at a position at least partially within said valvepassage;

C. withdrawing said end section from said end port by means forreciprocally transporting said shaft, thereby permitting flow of solubleliquefied gas from said end port directly into the stream of solventflowing within said valve passage;

D. passing resulting liquid from said valve passage through mixing meansenhancing dispersion of the soluble liquefied gas dissolving in saidsolvent;

B. establishing a liquid processing medium at a pressure substantiallybelow the pressure of the liquid flowing from said mixing means; and

F. passing liquid from said mixing means and feeding same through anozzle assembly directly into the liquid processing medium.

2. a single-seated valve assembly, having a valve passage therethrough forming a part of said conduit, said valve assembly having means whereby a controlled flow of soluble liquefied gas is introduced directly into said stream of solvent flowing within said passage;
 2. a second annular member positioned coplanar and coaxial with said first annular member and having an inner diameter substantially greater than the outer diameter of said first annular member thus providing an annular opening between said members;
 2. The dispersing apparatus of claim 1 wherein said mixing means is hydraulic and comprises a column containing spaced-apart plates, each plate being positioned partly to completely within said column and at least substantially transverse to the direction of flow of liquid therein, each plate containing at least one aperture whereby said liquid flows through said plate.
 3. radial flanges each engaging both said first and second annular members along the radial side surfaces thereof across said annular opening, thereby enclosing the opening; and
 3. mixing means downstream from said valve assembly, enhancing dispersion of the soluble liquefied gas dissolving in said solvent; and
 3. The dispersing apparatus of claim 1 wherein said liquid processing medium flows through a second conduit and said nozzle assembly comprises at least one disperser ring, around the second conduit, and comprising:
 4. The dispersing apparatus of claim 1 wherein the end section of said valve assembly shaft comprises a finger extending from a shoulder around said shaft, said finger being insertable within said end port and having at least one nonbeveled surface adapted to provide snug contact between said finger and the surface of said end port until complete removal of the finger therefrom, said shoulder having at least one surface in coplanar relation with the end surface of the valve seat, whereby said shoulder seals said end port when said coplanar surface abuts firmly against the end surface of the valve seat.
 4. inlet means for feeding the resulting solution from said mixing means into said annular opening, whereby it flows through the slot of the first annular member and into the liquid processing medium passing through the second conduit.
 4. a nozzle assembly downstream from said mixing means for passing the resulting solution into said liquid processing medium; wherein said single-seated valve assembly comprises: A. a valve body having a valve passage therethrough, connecting spaced apart inlet and outlet ports, and forming a portion of said conduit; B. a first hollow side protrusion extending outwardly from said body between said ports; C. a seCond hollow side protrusion extending outwardly from said valve body, at least substantially coaxial with said first protrusion and opposite same across said valve passage; D. a substantially rigid, stationary valve seat forming with said first protrusion a side passageway terminating in an end port opening at an end surface of said seat, said end surface being positioned so that said end port opens directly into said valve passage at least along a wall thereof; E. a movable shaft within said second protrusion, opposite side end port across said valve passage, said shaft terminating in an end section adapted for at least partial insertion within said end port and for sealing thereof, said end section having at least one beveled surface longitudinally along same providing diminishing cross-sectional area for the end section toward the end port; and F. means for reciprocally transporting said shaft to remove and insert said end section within the end port; whereby said end section seals said end port when in snug engagement therewith, and the beveling of said end section permits fluid to flow from said end port into said valve passage in amounts increasing with the increasing removal of said shaft from the side passageway.
 5. The method for first dissolving a soluble liquefied gas into a liquid solvent while permitting at least essentially full pressure on the liquefied gas to the zone of incipient solution, and thereafter dispersing the resulting solution into a liquid processing medium with accompanying pressure drop, while suppressing vaporization of gas as said liquefied gas dissolves in said solvent and as the resulting solution disperses in said liquid processing medium which method comprises: A. passing said liquid solvent within a valve passage housed in a valve body, at A pressure substantially as great as, to higher than, the vapor pressure of said liquefied gas at the temperature of said liquid solvent; B. feeding soluble liquefied gas into a side passageway of said valve body at a pressure above that of the liquid solvent in the valve passage and into contact with a shaft end section sealing an end port of said side passageway at a position at least partially within said valve passage; C. withdrawing said end section from said end port by means for reciprocally transporting said shaft, thereby permitting flow of soluble liquefied gas from said end port directly into the stream of solvent flowing within said valve passage; D. passing resulting liquid from said valve passage through mixing means enhancing dispersion of the soluble liquefied gas dissolving in said solvent; E. establishing a liquid processing medium at a pressure substantially below the pressure of the liquid flowing from said mixing means; and F. passing liquid from said mixing means and feeding same through a nozzle assembly directly into the liquid processing medium. 